<template>
  <div :class="classes" @mouseleave="handleMouseleave">
    <input type="hidden" :name="name" :value="currentValue">
    <div v-for="item in count" :class="starCls(item)" @mousemove="handleMousemove(item, $event)" :key="item" @click="handleClick(item)">
      <template v-if="!showCharacter">
        <span :class="[prefixCls + '-star-content']" type="half"></span>
      </template>
      <template v-else>
        <span :class="[prefixCls + '-star-first']" type="half">
          <template v-if="character !== ''">{{ character }}</template>
          <i v-else :class="iconClasses" type="half"></i>
        </span>
        <span :class="[prefixCls + '-star-second']">
          <template v-if="character !== ''">{{ character }}</template>
          <i v-else :class="iconClasses"></i>
        </span>
      </template>
    </div>
    <div :class="[prefixCls + '-text']" v-if="showText" v-show="currentValue > 0">
      <slot><span>{{ currentValue }}</span> <span v-if="currentValue <= 1">{{ t('i.rate.star') }}</span><span v-else>{{ t('i.rate.stars') }}</span></slot>
    </div>
  </div>
</template>
<script>
import Locale from '../../mixins/locale';
import Emitter from '../../mixins/emitter';
import mixinsForm from '../../mixins/form';

import Icon from '../icon/icon.vue';

const prefixCls = 'ivu-rate';

export default {
  name: 'Rate',
  mixins: [Locale, Emitter, mixinsForm],
  components: { Icon },
  props: {
    count: {
      type: Number,
      default: 5
    },
    value: {
      type: Number,
      default: 0
    },
    allowHalf: {
      type: Boolean,
      default: false
    },
    disabled: {
      type: Boolean,
      default: false
    },
    showText: {
      type: Boolean,
      default: false
    },
    name: {
      type: String
    },
    clearable: {
      type: Boolean,
      default: false
    },
    character: {
      type: String,
      default: ''
    },
    icon: {
      type: String,
      default: ''
    },
    customIcon: {
      type: String,
      default: ''
    }
  },
  data() {
    return {
      prefixCls: prefixCls,
      hoverIndex: -1,
      isHover: false,
      isHalf: this.allowHalf && this.value.toString().indexOf('.') >= 0,
      currentValue: this.value
    };
  },
  computed: {
    classes() {
      return [
        `${prefixCls}`,
        {
          [`${prefixCls}-disabled`]: this.itemDisabled
        }
      ];
    },
    iconClasses() {
      return [
        'ivu-icon',
        {
          [`ivu-icon-${this.icon}`]: this.icon !== '',
          [`${this.customIcon}`]: this.customIcon !== ''
        }
      ];
    },
    showCharacter() {
      return this.character !== '' || this.icon !== '' || this.customIcon !== '';
    }
  },
  watch: {
    value(val) {
      this.currentValue = val;
    },
    currentValue(val) {
      this.setHalf(val);
    }
  },
  methods: {
    starCls(value) {
      const hoverIndex = this.hoverIndex;
      const currentIndex = this.isHover ? hoverIndex : this.currentValue;

      let full = false;
      let isLast = false;

      if (currentIndex >= value) full = true;

      if (this.isHover) {
        isLast = currentIndex === value;
      } else {
        isLast = Math.ceil(this.currentValue) === value;
      }

      return [
        {
          [`${prefixCls}-star`]: !this.showCharacter,
          [`${prefixCls}-star-chart`]: this.showCharacter,
          [`${prefixCls}-star-full`]: (!isLast && full) || (isLast && !this.isHalf),
          [`${prefixCls}-star-half`]: isLast && this.isHalf,
          [`${prefixCls}-star-zero`]: !full
        }
      ];
    },
    handleMousemove(value, event) {
      if (this.itemDisabled) return;

      this.isHover = true;
      if (this.allowHalf) {
        const type = event.target.getAttribute('type') || false;
        this.isHalf = type === 'half';
      } else {
        this.isHalf = false;
      }
      this.hoverIndex = value;
    },
    handleMouseleave() {
      if (this.itemDisabled) return;

      this.isHover = false;
      this.setHalf(this.currentValue);
      this.hoverIndex = -1;
    },
    setHalf(val) {
      this.isHalf = this.allowHalf && val.toString().indexOf('.') >= 0;
    },
    handleClick(value) {
      if (this.itemDisabled) return;
      //value++;
      if (this.isHalf) value -= 0.5;

      if (this.clearable && Math.abs(value - this.currentValue) < 0.01) {
        value = 0;
      }

      this.currentValue = value;
      this.$emit('input', value);
      this.$emit('on-change', value);
      this.dispatch('FormItem', 'on-form-change', value);
    }
  }
};
</script>
